ConCom questions safety, effectiveness of bluff terracing

Friday

Jun 15, 2007 at 2:00 AM

By Margaret Carroll-Bergman I&M Staff Writer

With more than 30 percent of the anti-erosion wood terracing along the face of Sconset Bluff washed away during the April 16 “Patriot’s Day” storm, Nantucket Conservation Commission members are questioning the safety and the effectiveness of the beach preservation project in the wake of not one, but two nor’easters since March.

“Wouldn’t this be called a failure where 30 percent was removed?” asked commissioner Sarah Oktay.

The permits for the bluff-terracing project, which is a crude forerunner to the larger Sconset Beach Preservation Fund (SBPF) plan to mine 2.6 million cubic yards of sand off Sankaty Head and dump it along a three-mile stretch of beach, were extended for another 18 months in February with the caveat that as the sandbags made out of coir fiber – the husks of coconut shells – give out, that they be replaced by larger jute bags which are stitched together and anchored by steel cables and posts in the sand.

“One of my concerns is that we’ve put a lot of material into the near-shore environment and it is not sufficient in protecting the homes,” said Oktay, the director of the UMass-Boston Nantucket Field Station in Quaise.

Oktay also recognized that the data provided by SBPF engineers was insufficient to determine whether the terracing had protected the bluff and beach against storm events. Mark Ritz, SBPF project scientist from Epsilon Associates, said 864,000 linear feet of coir fabric and 250 to 325 wooden posts were washed out to sea.

“That amount is quite significant,” said Oktay. “How much of that did you physically recover?”

Ritz was unable to give a linear amount of fabric and the number of posts, saying that he could give the amount of the debris in truckloads or weight.

As part of the Order of Conditions for the extended permit, SBPF will be heat branding the initials “SBPF” on all pieces of wood and branding all the jute fabric with orange stitching running through it.

Ritz says the engineers are implementing a new reporting system to recover what had been lost, including measuring pieces of fabric as the jute is recovered.

Sconset Beach Preservation Fund officials submitted a post storm report on May 17, 2007, as required and filed a second report addressing Conservation Commission questions. Conservation commissioner chair woman, Virginia Andrews expressed concern that large chunks of the bluff fell off during the April storm and questioned if that was due to water collecting within the terracing.

“We don’t think the rainfall in the April storm caused the slumping. The sand in the terraces is beach sand and water percolates through it,” said Ritz. “Prior to the March storm, the wooden boards on the side of the terracing were removed, leaving only the front boards.”

William Hunter, attorney for SBPF, said the new design, which was permitted in February has 25 to 30 percent less wood and 70 percent less fabric.

“We are hoping, based on the new design, less material will be broadcast into the system,” said Hunter.

The wood and the jute from the April 16th storm traveled around the island with debris being reported on Coatue, Hummock Pond, Great Point, and the bulk of it washing up in Sconset and Codfish Park.

Edith Ray, an island bird expert, said that as the COIR bags unraveled in the ocean, they wrapped around other marine debris, such as roping, fishing lines and deck chairs, causing big balls of stuff which either floated around in the water or washed up on the beach. “One of my concerns is often it (the debris) gets buried before it can be found is uncovered during another storm,” said Andrews.

Conservation Administrator, Dirk Roggeveen, reminded commissioners their enforcement powers did not extend into public safety.

“Conservation commissions are not public safety agencies,” said Roggeveen. “We are focused on protecting the natural environment.”

Oktay said, “We can’t permit a project that is harmful to human life. We would not voluntarily permit something that could be dangerous.”

The SBPF will be coming before the Conservation Commission in the next couple of weeks to discuss the amended Order of Conditions for the extended permit and was asked to provide more detailed information about the terracing project and how it has stemmed or contributed to the erosion along the beach.

Never miss a story

Choose the plan that's right for you.
Digital access or digital and print delivery.

Original content available for non-commercial use under a Creative Commons license, except where noted.
The Inquirer and Mirror ~ One Old South Road, Nantucket, MA 02554 ~ Privacy Policy ~ Terms Of Service